2.3. CTRP9 Pre-Treatment of VSMCs
Recombinant human CTRP9 (R&D Systems, Minneapolis, MN, USA) was reconstituted at a concentration of 250 μg/mL in sterile PBS and diluted to different concentrations in SMCGS-free SMCM. After cell synchronization, VSMCs were incubated with fresh serum-free medium containing CTRP9 at the indicated concentrations such as 0.1, 1, and 10 µg/mL, and cultured for 30 min before ox-LDL treatment.